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Loud secondary air pump

30133 Views 65 Replies 12 Participants Last post by  vaboxr
My 97-528 SAP is kind of loud compares to my 02-530.
It's a fast loud thumping sound.
I think the air passage may have been clogged, but then again this maybe normal for 528.
How's every 528 SAP sound in the morning? Thanks for the feed back.
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16valex, how are things with your SAP nowadays?

I noticed my pump a few times (many months ago) to be quite noisy on -some- occasions, not always
(more of a loud electrical buzz than a choo-choo), but in recent months I've heard nothing from it. Maybe it is dead...

My car starts fine, runs fine, no CELs, nothing ... but the silence is worrisome. Time to diagnose but wanted to get some clarification with the Seafoam.

If you are running Seafoam through the valve, does it go straight into the cats (ex. manifold) and out the exhaust? Or into the cylinders/valvetrain at all?

My pump has recently started making this loud humming noise at cold start-up in the mornings as well...
I plan on cleaning the Valve per JimLev's writeup...
My SAP pump and valve is less than two years old. The loud thumping sound is still there. I'm pissed.

I also replaced the damn electric switch. Every thing is working, but what pisses me off is the loud thumping is still there and to add to the madness I have a have CEL on for SAP. :mad::mad::mad:... I just ignore the bastard.

However, I just ordered a new pressure hose for 27 dollars, it's not too expensive, I'm going to replace this hose soon.

I think you were on to something there with the problem possibly being a gunked-up exhaust manifold...
Ever think about the POST-cat Oxygen Sensors being bad...?

Just a thought...

Oh my gosh!!!! Live and learn everyday on these cars.

So I was waiting for my SAS pressure hose to arrive, but just for giggle one cold morning I removed the SAP hose from the air valve during a cold start, to my very surprise there was nothing coming out of the hose, which can only means my SAP is dead!!!!

So, the thumping noise I heard was actually came from the exhaust back into the pump, all this time I thought something in the exhaust manifold is clogged...DUH!!!

Found the cheapest new Pielburg pump on the internet for 200 bucks from BMA, installed the pump along with the new pressure hose. No more thumping sound. :thumbup:
WOW! :yikes:
Yeah man, the fact that I had to shed out 200 bucks which I wasn't to happy for something that has no effect to the engine's performance other than drawing air to dilute emission gases during a cold start. But in a way I'm also happy to have put this thumping sound to rest and no more SAS codes.
Yep, I am sorry that you had to spend $200...

I am not sure if you mentioned it or not, but, did you have a check engine light on?

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